Pneumatic hydraulic vise



June 25, 1963 H. w. M. FREUND 3,095,190 PNEUMATIC HYDRAULIC VISE FiledSept. 7, 1961 2 Sheets-Sheet 1 INVENTOR. HANS W. M. FREUND June 25, 1963H. W. M. FREUN D PNEUMATIC HYDRAULIC VISE 2 Sheets-Sheet 2 Filed Sept.'7, 1961 INVENTOR. HANS W. M. FREUND Unite States atent 3,095,190PNEUMATIC HYDRAULIC VISE Hans W. M. Frennd, Hilchenbach, Westphalia,Germany,

assignor to Maschinenfabrik Hilma G.m.b.H., Hllchenbach, Westphalia,Germany Filed Sept. 7, 1961, Ser. No. 136,624 Claims priority,application Germany Sept. 10, 1960 4 Claims. (Cl. 26928) The presentinvention relates to a pneumatic hydraulic vise in which the compressedair acts through the intervention of a pressure transformer on apressure fluid which in its turn adjusts the vise jaw.

Vises which are adjusted directly by compressed air are known in theart. The drawback of this heretofore known type of vise consists in thatdue to the relatively low pressure of the customary prevailingcompressed air installation and due to the direct actuation of the airpiston, relatively large cylinder dimensions and consequently relativelylarge dimensions for the vise or clamping apparatus are necessary. Visesoperable by compressed air of the size of the customary mechanical viseshave a low clamping power.

Compressed air actuated vises have become known heretofore in which thepiston conveys its clamping force to the movable jaw through theintervention of a lever system. While with this type of vises higherclamping forces can be produced, these known clamping devices have thedrawback of a very short stroke, inasmuch as the stroke of the movablejaw hardly exceeds a few millimeters. Also with this type of vise, thedimensions are prohibitive if customary clamping forces are to beproduced.

Furthermore, pneumatic hydraulic Vises have become known in which asmall pressure transformer is installed in the lower portion of thevise. With these vises, the movable jaw is first advanced toward thework piece until it is spaced therefrom by a few millimeters, whereupona pressure valve is opened which initiates the clamping operation andafter a dead stroke exerts the desired clamping force. These clampingdevices have the drawback that they consume the major portion of thepressure for overcoming the dead stroke.

Pneumatic hydraulic vises in which the pressure transformer is locatedoutside the vise have additionally to establish the connection betweenpressure transformer and vise through the intervention of a highpressure hose. Such high pressure hoses are undesired and are verysensitive against bending stresses.

It is, therefore, an object of the present invention to provide apneumatic hydraulic vise which will overcome the above mentioneddrawbacks.

It is another object of this invention to provide a pneumatic hydraulicvise which will make it possible mechanically to feed the movable jaw tothe work piece and then to initiate an automatic pneumatic hydraulicclamping action.

These and other objects and advantages of the invention will appear moreclearly from the following specification in connection with theaccompanying drawing, in which FIG. 1 shows a pneumatic hydraulic viseaccording to the present invention. FIG. 2 shows the right-hand portionof FIG. 1 but with the respective elements occupying a position in whicha work piece is in clamped-in position.

The pneumatic hydraulic vise according to the present .invention ischaracterized primarily in that a manually operable feeding spindle isprovided with a jaw clutch comprising a first jaw clutch element and asecond jaw clutch element and also including an axially displaceable jawshaft which latter is connected to a control shaft for an aircontrolling valve. By means of an arrangement upon a ball 18 which islocated 3,095,190 Patented June 25, 1963 ,pressure transformer, i.e. theair actuated piston, with the hydraulic piston in the movable jawwhereby a compact construction of the vise will be obtained.Advantageously, the pressure transformer may be arranged adjacent theclamping piston but it may also be arranged laterally of the spindle inthe movable jaw.

Specifically referring to the drawing, the vise illustratedthereincomprises a stationary jaw 1 and a movable jaw 1a provided with.a larger cylinder bore 3a and a smaller cylinder bore 6a. Reciprocablymounted in the cylinder bore 3a is a compressed air operable piston 3the upper sideof which communicates through a passage 4 with a.compressed air valve block 5. The piston 3v has connected thereto ahydraulic plunger 6 reciprocably mounted in cylinder 6a. The hydrauliccylinder 6a is connected through a passage or oil chamber 30 with acylinder 7a in which is reciprocably mounted the clamping piston 7. Theclamping piston 7 has a bore 712 in which is reciprocably mounted thefront portion 8a of a spindle v8 the thread 812 of which engages acorrespondingly threaded bore 912 of a member 9 which latter is anchoredin the lower portion 31 of the vice by means of a bolt 9a.

The vice according to the present invention furthermore comprises abearing plate 10 having journalled therein a clutch shaft 11 by means ofa needle bearing 10a. Furthermore displaceably mounted in bearing plate10 is a guiding bushing 12 which in its turn has movably mounted thereinone end portion 13b of a control A compression spring 14 is interposedas yieldable member between the end member 13b of the control shaft 13and the guiding bushing 12.

V 'The clutch shaft 11 has its right-hand portion with regard to thedrawing journalled on a thrust bearing 15 which is acted upon by aspring 16 that has that end thereof which is remote from the thrusthearing 15 rest upon a lid 17. The jaw shaft 11 has a circumferentialgroove 11b which is engaged by a flange, disc, or collar 13a of controlshaft 13.

The guiding bushing 12 is adapted to engage and act in an abutmentbushing 19, said ball being acted upon by a spring 20. This spring 20rests against a valve disc 21 connected to a valve disc 23 through theintervention of the valve shank 22. Valve disc 23 is acted upon by aspring 24.

The valve block 5 has mounted therein a nipple 35 to which is connectedthe mouth of a hose 25, said nipple and hose being shown in the drawingturned by The clutch shaft 11 is adapted to receive a manually operablecrank 26 for actuating the same.

The operation of the vise according to the present invention is asfollows: i

If a work piece is to be clamped between the stationary jaw '1 and themovable jaw 10, first the crank 26 is turned manually whereby due to thejaw clutch engagement of clutch shaft 11 with the spindle 8 also thelatter will assuming a corresponding direction of rotation of the handle26. When the movable jaw 1a has engaged the a another clutch memberforming part of or being connected to the spindle 8. As a resultthereof, the clutch shaft 11 will move axially away from the spindle 8against the thrust of compression spring 16. Due to this axial movementof the clutch shaft 11, also the control shaft 13 is, due to theengagement of disc 13a with groove 11b of clutch shaft 11, axially movedin the same direction as clutch shaft '11. This movement of controlshaft 13 is conveyed through pressure spring 14, ball 18 and pressurespring 20 to the valve disc 21 so as to move the latter in rightwarddirection with regard to the drawing against the valve seat 28 whileovercoming the thrust of pressure spring 24. Simultaneously with theseating of valve disc "21 upon valve seat 28, valve disc 23, throughvalve shank 22, is lifted off its seat 29. The stroke of the guidingbushing 12 is limited by the abutment bushing 19.

Due to the lifting off of valve disc '23 from its seat 29,

compressed air will pass through hose 25 into the passage 4 leading topiston 3 thereby actuating the pressure transformer 3, 6.

In conformity with the ratio between the effective area of piston'3 andthe effective area of the hydraulic plunger 6, the pressure in theoilchamber 'will increase. This.

increase in pressure will be conveyed to the eflective surface of theclamping piston 7with'the're-sult that the movable jaw 1a is pressed inclamping direction indicated by the'arrow A whereby the work piece willbe firmly clamped between the jaws of the vise. It will be appreciatedthat during this clamping operation, the axial position of themechanical drive not dhangedjand that merely thetspring 1-4 iscompressed and thus serves as compensating device.

from the fixed jaw, it is merely necessary to turn the crank 26in adirection opposite to its clamping direction whereupon the jaw member 33will slide ofl the inclined surface 27of, the other jaw member. Theclutch shaft 11 will in this way by means of spring 16 be displaced inaxial direction (toward the left with regard to the drawing). In view ofthe connection of the control shaft 13 with the jaw shaft 11 through theintervention of the collar or disc 13a, also control shaft 13. willmovein leftward direction with regard to the drawing. Consequently, valvedisc 23 will, due to the thrust of pressure spring 24 again becomeseated on valve seat 29 with the result that the supply of furthercompressed air to the passage'4 will be blocked. Valve disc 21 will,during this movement release a discharge opening 34 through which theair from the pressure transformer can escape toward the outside throughpassage 4. By further rotat- -ing crank 26, it is then possible to openjaw 1 to the desired extent. This unclamping operation takes aboutone'second.

It is, of course, to be understood that the present invention is, by nomeans, limited to the particular construction shown in the drawing butalso comprises any modifications within the scope of the appendedclaims. Thus, for instance, instead of mechanically driving the spindle8 by hand, it is, of course, also possible to drive the spindle by anelectric motor. In such an instance, the control shaft 13 would beprovided with limit switches for controlling the drive motor for thespindle 8.

What I claim is:

:1. In a vise:v a stationary jaw, a movable jaw for cooperation withsaid stationary jaw, mechanical means mechanically drivingly connectedto said movable jaw and operable mechanically to move said movable jaw 4selectively toward and away from said stationary jaw, said mechanicalmeans comprising a first member with a first jaw clutch element and alsocomprising a second member movable relative to said first member andprovided with a second jaw clutch element for engagement and cooperationwith said first jaw clutch element, said second jaw clutch element beingadapted in response-to a certain torque acting thereupon to ride on saidfirst jaw clutch element to thereby impart a certain axial movement uponsaid second member, fluid operable pressure transformer meansoperatively connected to said movable jaw and operable in response tofluid pressure acting upon said transformer means to move said movablejaw toward said stationaryjaw, conduit means leading to said pressuretransformer means and arranged for connection with a pressure fluidsource, and valve means interposed in said conduit means and movableinto a first position for conveying pressure fluid to said pressuretransformer means and also being movable into asecond position forpreventing the supply of pressure fluid to said pressure transformermeans while releasing the fluid pressure thereon, said valve meansincluding control means operatively connected to said second member andresponsive to said axial movement in view of said certain torque formoving said valve means into said first position.

selectively toward and "away from saidsta tionary jaw,

said mechanical means comprising a' firstmerriber with a first jawclutch element and also comprising a second member movable relative tosaid first member and provided with a second'jaw clutch element forengagement and cooperation with said first jaw clutch element, saidsecond jaw clutch element being adapted in response to a certain torqueacting thereupon to ride on said first jaw clutch element to therebyimpart a certain axial movement upon said second member, a pneumaticcylinder piston system arranged within said movable jaw, a hydrauliccylinder piston system operatively connected to said pneumatic cylinderpiston system and likewiselocated in said movable jaw and operable toactuate the latter in response to the operation of said pneumaticcylinder piston system, conduit means leading to said pneumatic cylinderpiston system for connection with a source of compressed air, and valvemeans interposed in said conduit means and movable into a first positionfor conveying compressed air to saidpneumatic cylinder piston system andalso being movable into a second position for preventing the supply ofcompressed air to said pneumatic cylinder piston systern whil-ereleasing the pneumatic pressure thereon, said valve means includingcontrol means .operatively connected to said second member andresponsive to said axial movement in view of said certain torque formoving said valve means into said first posi- References Cited in thefile of this patent UNITED STATES PATENTS 2,402,411 =Kent June 18, 19462,492,338 'Vickers Dec. 27, 1949 2,509,991 Schenke May 30, 1950

1. IN A VISE: A STATIONARY JAW, A MOVABLE JAW FOR COOPERATION WITH SAIDSTATIONARY JAW, MECHANICAL MEANS MECHANICALLY DRIVINGLY CONNECTED TOSAID MOVABLE JAW AND OPERABLE MECHANICALLY TO MOVE SAID MOVABLE JAWSELECTIVELY TOWARD AND AWAY FROM SAID STATIONARY JAW, SAID MECHANICALMEANS COMPRISING A FIRST MEMBER WITH A FIRST JAW CLUTCH ELEMENT AND ALSOCOMPRISING A SECOND MEMBER MOVABLE RELATIVE TO SAID FIRST MEMBER ANDPROVIDED WITH A SECOND JAW CLUTCH ELEMENT FOR ENGAGEMENT AND COOPERATIONWITH SAID FIRST JAW CLUTCH ELEMENT, SAID SECOND JAW CLUTCH ELEMENT BEINGADAPTED IN RESPONSE TO A CERTAIN TORQUE ACTING THEREUPON TO RIDE ON SAIDFIRST JAW CLUTCH ELEMENT TO THEREBY IMPART A CERTAIN AXIAL MOVEMENT UPONSAID SECOND MEMBER, FLUID OPERABLE PRESSURE TRANSFORMER MEANSOPERATIVELY CONNECTED TO SAID MOVABLE JAW AND OPERABLE IN RESPONSE TOFLUID PRESSURE ACTING UPON SAID TRANSFORMER MEANS TO MOVE SAID MOVABLEJAW TOWARD SAID STATIONARY JAW, CONDUIT MEANS LEADING TO SAID PRES-